I like ironwood, but I don't use it very frequently because good pieces are expensive, it requires sharp tooling, and it dulls tooling quickly.
For knives I sell, I like cocobolo and African blackwood. They're attractive, reasonably priced, don't tear up cutters too fast, machine well, and dimensionally stable. You do have to be careful with dust from cocobolo, it is a skin sensitizer.
Personally, I like Osage orange. It is tough, stable, durable, grippy when covered in goo. The problem is, it doesn't attract a lot of buyers because it isn't real pretty. I think of it as natures micarta. Most people looking for something like that just want micarta, but I just love a good piece of plain sawn (tangential grain) osage orange.
I've been working a lot of G10 this week. I hate that stuff, it eats up tooling and deposits a fine layer of sand everywhere. I'll be pumping some sumps on Monday...